Particulate material conveying system



Jan. 31, 1967 c. E. BERRY 3,301,504

PARTICULATE MATERIAL CONVEYING SYSTEM Filed March 14, 1966 2 Sheets-Sheet l Fzzytj.

.9 INVENTOR Cyamzs E BERRY.

7 I ,Byfiwfl ATToRNEYj Jan. 31, 1967 c BERRY PARTICULATE MATERIAL CONVEYING SYSTEM 2 Sheets-Sheet 2 Filed March 14, 1966 fig INVENTOR CHARLES E BERRY.

QZLFQMJ ATTORNEY} United States Patent M 3,301,604 PARTICULATE MATERIAL CONVEYING SYSTEM Charles E. Berry, Fairmont, W. Va., assignor to Viking Corporation, Bristol, Tenn., a corporation of Tennessee Filed Mar. 14, 1966, Ser. No. 534,146 6 Claims. (Cl. 302--24) This invention relates to improvements in particulate material conveying systems.

This invention has been found to be particularly useful in conveying particulate materials for use with a coal washing system and it is shown and described as being used in such coal washing system. It is, however, to be understood that the invention is not limited to use with a coal washing system.

In coal washing systems, it is desirable to create a slurry having a higher specific gravity than that of the coal to be washed, and the coal is floated through this slurry in the washing thereof. As the coal is floatation washed, impurities adhering to the coal and having a higher specific gravity than the coal will fall to the bottom of the Washing apparatus as sediment, and may be removed from the system. It has been found that magnetite, prepared as a particulate material having generally the consistency of face powder, is particularly adaptable for intermixing with water in forming a slurry having a specific gravity which is higher than that of the coal to be washed. Use of magnetite has many advantages, as is Well known in the art, such as being readily separated from any coal to which it may adhere and the slurry which moved through the washer, by use of a magnet.

Inasmuch as the magnetite used in such coal washing operations is a particulate material having the consistency of face powder, many difficulties exist in connection with use of the same as an additive to the coal washing system. For instance, if particulate magnetite remains static in a relatively confined space, such as a pipe of small diameter such as might be used to convey the same, it will become tightly packed to such an extent that it is necessary to disassemble the apparatus where the packing occurs in order to remove the packed magnetite.

Some operators provide a large tank or container, filled with magnetite, at the uppermost reaches of the coal washing tipple, and feed the same into the coal washing system as required. This results in a top-heavy tipple and puts the storage container in a difficult position for refill- Previous methods have also taught the filling of a tank manually or automatically with the magnetite and then emptying it through a pipe line with air pressure active throughout the tank. Inasmuch as the particulate magnetite will pack tightly if it is not kept moving in the pipe line, it was necessary to provide continuous movement of the magnetite through the lines leading from the storage tank and into the coal Washing system. This was usually by way of high velocity, low pressure air lines over which constant supervision had to be maintained in order to prevent packing, and transfer of a considerable quantity of magnetite from the storage tank to the coal washing system became virtually mandatory for economical operation. Such previous methods have thus not provided a carefully regulated flow of magnetite such as is necessary to maintain the optimum specific gravity of the slurry in which the coal is washed.

The primary object of the present invention is the provision of a conveying system for particulate materials which permits conveying of the same at a carefully controlled rate, which enables relatively small quantities of material to be fed from a storage tank to a discharge area, and in which the likelihood of packing of the particulate material in the conveying lines is virtually eliminated.

Patented Jan. 31, 1967 A further object is the provision of a particulate material conveying system operating on a pulsing principle, in which a relatively small amount of particulate material is fed through the conveying system during each operating cycle, the conveying lines being cleared after each conveying operation, and in which pulsing system the cycles of conveying may be continuous or intermittent, as required.

A further object is the provision of a particulate material conveying system which embodies use of low pressure, high velocity pneumatics in the conveying of the particulate material which enables the same to be lifted to a considerable height, through the conveying lines, from storage apparatus located on the ground, in position to be readily refilled.

Other objects and advantages of the invention will become apparent during the course of the following detailed description, taken in connection will the accompanying drawings, forming a part of this specification, and in which drawings:

FIG. 1 is an overall illustration of my improved conveying system, the same being diagrammatic in part to fully illustrate the complete system.

FIG. 2 is an enlarged fragmentary transverse sectional view of the lowermost portion of the storage tank of my improved conveying system, showing the adjunct container thereof which receives relatively small quantities of the particulate material from the storage tank, which is the initial step in my conveying system.

FIG. 3 is a fragmentary sectional view similar to FIG. 2, showing the particulate material received in the container adjunct to the storage tank being blown therefrom under pneumatic pressure, to the discharge area of the conveying system.

FIG. 4 is an enlarged sectional view of the nozzle for introducing air under pressure to within the container adjunct to the storage tank.

FIG. 5 is a transverse sectional view taken substantially on the line 5-5 of FIG. 2.

FIG. 6 is an enlarged elevational view of a form of timer which may be used in regulating the pulsing cycles of my improved conveying system.

FIG. 7 is an enlarged view, partly in section, showing apparatus for control of discharge from the product collector, which is located at the discharge area of my conveying system.

FIGS. 8 and 9 are further views of the mechanism of FIG. 7, showing operation of the same in controlling release of particulate material from the product collector.

In the drawings, wherein for the purpose of illustration,

' is shown a preferred embodiment of the invention, and

wherein similar reference characters designate corresponding parts throughout the several views, the letter A may generally designate my improved conveying system which preferably includes a storage receptacle B; a container C adjunct to storage receptacle B for receiving a relatively small charge of particulate material from storage receptacle B; conduit means D interconnected with container C and leading to a discharge area; and pneumatic pressure means E operatively interconnected with container C for pneumatic pressurized discharge of a charge of particulate material from container C and through conduit means D to the discharge area thereof. Since the particulate material being conveyed may be in a powdered form which would create considerable dust if the discharge end of condiut means D were open, conduit means D is preferably provided, at the discharge area thereof, with a product collector F which may, for illustrative purposes, be positioned for discharge into a coal washer G.

Storage receptacle B preferably comprises a tank 15 having wall portions 16 which define a chamber 17 for receiving a considerable quantity of paflic'u'late material. Filler pipe 18 may be provided, leading into chamber 17, for filling of storage tank 15.

Inasmuch as the particulate material which is to be stored within storage tank 15 may have a tendency to become tightly packed if it is static within the storage tank, I preferably provide means whereby the particulate material within storage tank 15 may be kept continuously moving, for maintaining the same in what might be termed a fluidized state. To this end, storage tank 15 is preferably provided with a false bottom 20 having a plurality of air pads 21 thereon, a conduit 22 being provided throughout false bottom 20 for feeding of air to air pads 21, an air intake conduit 23 leading to conduit 22 from a compressor 24. It will thus be seen that compressor 24 provides a continuous flow of gas under pressure through conduits 23 and 22 to air pads 21, from which low pressure gas may be discharged at the lowermost end of chamber 17 for maintaining the particulate material contained therein in a substantially fluidized state.

Storage tank 15 may be provided with a vent 26 which enables the escape of air therefrom, and is of a type to permit expansion of air whereby any particulate material which may be carried upwardly thereto by the air pressure in storage tank 15 will be separated from the escaping air and drop back into chamber 17, as is well known in the art.

Container C preferably comprises an open ended small tank or vessel 30 having wall portions 31 providing a chamber 32 therewithin. The open end of tank 30 is welded or otherwise secured to a plate 33 which provides a closure over the open end thereof. The end of container C opposite plate 33 is provided with a port 36 to which conduit means D is attached, as will be subsequently described. Plate 33 is preferably provided with an intake conduit 37 interconnecting between storage tank 15 and container C which provides a passageway adjacent the lowermost portion of chamber 17 of storage tank 15 to facilitate substantial gravity flow of particulate material from chamber 17 of storage tank 15 to chamber 32 of container C, as shown in FIG. 2. Valve means 38 is mounted on wall or plate 33 within chamber 32 of container C for regulating flow of particulate material through interconnecting conduit 37.

Valve means 38 preferably includes attaching posts 40 for attachment thereof to plate 33, hinge 41 attached to posts 40, and a valve plate closure member 42 attached to hinge 41, in juxtaposition for closure of interconnecting conduit 37 under conditions as will be subsequently described. As shown in FIG. 2, valve means 38 is preferably normally open to permit substantial gravity flow of particulate material from chamber 17 of storage receptacle B to chamber 32 of container C.

Conduit means D preferably includes a pipe 45 having one end thereof attached to port 36 of container C, and the other end thereof leading to the discharge area of the conveying system, which, in the form illustrated, discharges into product collector F.

Pneumatic pressure means E preferably includes a compressor 50 and air nozzle 51, a conduit 52, being provided for conveyance of air under pressure from compressor 50 to air nozzle 51.

Air nozzle 51 is preferably welded or otherwise secured within chamber 32 of container C and includes an elongated, preferably tubular body portion 55 having a plurality of ports or outlets S6 spaced longitudinally therealong and an outlet 57 at one end thereof. Air nozzle 51 is preferably positioned within chamber 32 so that ports or outlets 56 discharge to within the main body of chamber 32 of container C, for agitating or causing movement of particulate material within chamber 32, and outlet 57 thereof is directed toward port 36 for directional discharge of air therefrom in propelling the particulate material from chamber 32 of container C through conduit means D.

As shown in FIG. 3, when air under pressure is expelled through nozzle 51, the increased pressure within chamber 32 of container C causes normally open valve means 38 to close, sealing off chamber 17 of storage receptacle B from chamber 32 of container C and segregating the particulate material within container C from the particulate material contained within storage receptacle B. With the particulate material of container C thus segregated from the particulate material of storage receptacle B, it is possible to eject, by air pressure flow through nozzle 51, all of the particulate material from container C and to interject sufiicient air pressure therewithin to substantially clear conduit means D of the particulate material. This enables a measured discharge of particulate material through the conveying system.

Pneumatic pressure means E may also include timer means 60 for automatically regulated operation thereof in regular cycles which include: opening of valve means 33, permitting filling of chamber 32 of container C with particulate material from storage tank 15; actuation of air nozzle 51, which closes valve means 38 and causes discharge of particulate material from container C through conduit means D, the operation of air nozzle 51 being preferably of a duration to substantially clear chamber 32 and pipe 45 of particulate material; and shutting off of air nozzle 51, which permits valve means 38 to resume its normally open position for gravity filling of chamber 32. This provides continuous cycles of filling and discharge of particulate material from chamber 32 of container C and a pulsing system of feeding of particulate material through the conveying system.

Timer means 60 preferably includes a solenoid valve 61, located in conduit 52 and regulating air flow therethrough, and an electrical timer 62. Lines 64 and 65 are provided leading from solenoid valve 61, line 64 leading to a power source and line 65 being provided with a first switch means 66 operable by timer 62, and second switch means 67 which may be manually operated, leading from switch means 67 to a power source common with line 64.

Timer 62 preferably includes a clock timer 70 having a variable speed disc 71 provided with cam members 72 and flats 73. Timer 62 operates in a conventional manner, in cooperation with switch means 66, switch means 66 being permitted to open when flats 73 are adjacent thereto and cam members 72 closing switch means 66. Thus, during operation of the timer, solenoid valve 61 will be closed when switch means 66 is in abutment with flats 73, at which time conduit 52 will be closed, and chamber 32 of container C permitted to fill with particulate material, and when cam members 72 abut against switch means 66, solenoid valve 61 will be opened, permitting air under pressure to flow through conduit 52 and out through air nozzle 51. I have thus provided a continuous pulsing system for conveying particulate material through the conveying system. When the timer 62 is in operation, switch means 67 will, of course, be automatically interlocked in closed position. Under some conditions of operation it may be desirable to bypass timer 62 and manually control flow of particulate material through the conveying system. In such instances, timer 62 will be positioned so that switch means 66 is closed, as shown in FIG. 6, and manual opening and closing of switch means 67 will thereby regulate operation of the conveying system.

Product collector F preferably includes a particulate material collecting portion 75 having a vent means 76 at the uppermost portion thereof and a discharge conduit 77 leading from the lowermost portion thereof, and is provided with discharge valve means 78 which regulates discharge of material therefrom through discharge tube 77.

In the form of product collector shown, discharge tube 77 is of resilient material, such as rubber, and valve '5 means 78 is designed to form a pinchcoc'k which is operable to close discharge tube 77. Valve means 78 preferably includes an air cylinder 79 and a closure mechanism 80 which may be mounted on a common supporting flange 81 attached to coal washer G.

Air cylinder 79- preferably includes a cylinder 82 having an intake port 83 and an outlet port 84. A piston 85 is mounted within cylinder 82 for reciprocatory movement therewithin, a spring 86 being provided in cylinder 82 urging piston 85 toward intake port 83, A connecting rod 87 is operatively connected at one end thereof to piston 85 and at the other end thereof to closure mechanism 80 in juxtaposition for actuation of closure mechanism 80 by air cylinder 79.

A conduit or pipe line 88 is preferably interconnected at one end thereof to intake port 83 and the other end thereof leads to an interconnection with conduit or pipe 52, for actuation of air cylinder 79 in accordance with the air pressure in pipe 52, as will be subsequently described.

Closure mech-anism 80 preferably includes a frame 90 having 'lever members 91 and 92 mounted thereon. Levers members 91 and 92 are respectively supported for pivotal movement on shafts 93 and 94, having respective lowermost intermeshing gear portions 95 and 96 and having respective roller members 97 and 98 attached to the uppermost portions thereof. Shafts 93 and 94 are journaled on frame 90 with their axes posit-ioned thereon for parallel rotation, lever members 91 and 92 being supported thereon sothat roller members 97 and 98 abut opposite sides of discharge tube 77. A connector 99 is provided between shaft 87 and lever 91, gear portions 95 and 96 meshing so that pivotal movement of roller member 97 of lever member 91 toward or away from discharge tube 77 will cause a like movement of roller member 98 of lever member 92.

As shown in FIG. 8, valve means 78 is normally open. Upon introduction of air under pressure through pipe line 88, shaft 87 of air cylinder 79 will be extended causing lever members 91 and 92 to pivot with the respective roller members 97 and 98 thereof moving toward one another to squeeze discharge tube 77 closed, as shown in FIG. 8. Upon relaxationof air pressure in pipe line 88, spring 86 of air cylinder 79 will cause retraction of shaft 87, moving roller members 97 and 98 away from discharge tube 77 to normally open position as shown in FIG. 8.

Coal washer G is only diagrammatically shown as including a tank 100 which receives a slurry 101.

In operation of my improved conveying system, compressor 50 and timer means 60 will first be actuated. In this operation of the conveying system, it will be assumed that switch means 67 is interlocked in a closed position, and that control of flow through the conveying system will be by way of timer 6-2.

As flats 73 of variable speed disc 71 of timer 62 are in abutment with switch means 66, switch means 66 will be open, which means that solenoid valve 61 in pipe line 52 will be closed. Under this condition, there will not be any air flowing into air nozzle 51 and none will be flowing through pipe line 88. Accordingly, normally open valve means 38 in container C will be open, permitting substantial gravity flow of particulate material from storage receptable B to container C. There will likewise not be any air flow to air cylinder 79, and closure 'mechanism 80 will be open, permitting discharge of material from product collector F through discharge tube 77 and into coal washer G.

When cam members 72 abut switch means 66, switch means 66 will be closed, which opens solenoid valve 61. At this time, air is permitted to flow from compressor 50 through pipeline 52. Air flowing through pipe line 52 will be introduced into air nozzle 51, and through ports 56 thereof which will agitate particulate material within container C and raise the air pressure therewithin to an extent whereby valve means 38 is closed. Air will also flow through outlet 57 of air nozzle 51, which will propel the particulate material from container C and through pipe line 45 to particulate material collecting portion 75. As previously stated, air flow through pipe line 52 is preferably of a volume and duration to substantially clear container C of all particulate material therein and to also clear pipe line 45.

Air also flows from pipe line 52 and through pipe line 88 to air cylinder 79. When the same reaches air cylinder 79, piston thereof will be moved, causing closure of mechanism 80, which closes discharge tube 77. Thus, discharge tube 77 will be closed during the entire time that particulate material is delivered into particulate material collecting portion 75 of product collector F. Thus, any dust which is created in the delivery of particulate material from container C to product collector F will be permitted to gather within product collector F and settle.

As variable speed disc 71 of timer 62 moves further, a flat 73 thereof will again abut switch means 66, permitting the same to open, which closes solenoid valve 61. Upon closure of solenoid valve 61, air flow to air nozzle 51 is cut off, which permits opening of normally open valve means 38, permitting substantial gravity flow of particulate material from storage receptacle B to storage receptacle C. This will likewise cut off air flow through pipe line 88 to air cylinder 79, and spring 86 thereof will return piston 85 to its normal position, which causes opening of closure mechanism 70 so that particulate material which has been previously deposited in particulate material collecting portion 75 of product collector F will be permitted to discharge therefrom through discharge tube 77 and into coal washer G.

The system may be continuously operated in order to provide a conveying of as much particulate material as is required at any given time or continuously.

Throughout this specification, the conveying system has been described as being operable through air pressure. It is, however, to be understood that various other gases might be used in operation of the system.

Various changes may be made to the form of the invention herein shown and described without departing from the spirit of the invention or the scope of the following claims.

I claim:

1. In a conveying system for particulate material, the combination of a particulate material storage receptacle including means for aerating the particulate material received therewithin and maintaining the same in a sub stantially fluidized state; a container for receiving a relatively small charge of particulate material from said storage receptacle; means interconnecting said container with said storage receptacle in juxtaposition for gravity flow of particulate material from said storage receptacle to said container; check valve means for segregating the charge of particulate material of said container from the particulate material of said storage receptacle; conduit means interconnected with said container and leading to a discharge area; and pneumatic pressure means operably interconnected with said container for pneumatic discharge of a charge of particulate material from said container and through said conduit means to a discharge area under sufficient pressure to substantially clear said container and said conduit means of particulate material, said pneumatic pressure means including an elongated air nozzle mounted within said container and having a plurality of air discharge apertures spaced therealong in juxtaposition for substantial aeration and fluidizing of the particulate material charge of said container on activation of said pneumatic pressure means, and said check valve means comprises means for preventing back flow of air and particulate material from 7 7 said container to said storage receptacle on activation of said pneumatic pressure means.

2. In a conveying system for particulate material, the combination of a particulate material storage receptacle including means for aerating the particulate material received therewithin and maintaining the same in a substantially fluidized state; a container attached to said storage tank, said container including a chamber for receiving a charge of particulate material comprising a fraction of the volume of said storage tank; a passageway interconnecting between said storage tank and said chamber of said container, said container and said passageway being positioned with respect to said storage tank for substantial gravity flow of said particulate material from said storage tank to the chamber of said cntainer; normally open check valve means mounted in said chamber and positioned for opening and closing said passageway; an elongated air nozzle mounted within said chamber; air supply means interconnected with said air nozzle for supplying air thereto under relatively high pressure; a conduit opening into and leading from said chamber to a discharge area, said elongated air nozzle including a plurality of outlets spaced longitudinally therealong and an outlet at one end thereof, said air nozzle being juxtaposed within said chamber for discharge of air from said plurality of longitudinal outlets within the main body of said chamber in juxtaposition for substantial aeration and fiuidizing of the particulate material in said chamber of said container on activation of said air supply means, and said end outlet thereof being directionally positioned for discharge of air at the locus of the opening of said conduit leading from said chamber, said air supply means being operable to furnish air under pressure to said air nozzle at a sufiicient pressure to substantially clear a charge of particulate material from said chamber, said valve means being operable to close said passageway under the effect of increased air pressure in said chamber created by air flow through said air nozzle from said air supply means; and timer means operably interconnected with said air supply means for providing spaced pulses of air to said chamber, said timer means being correlated to regulate pulses of air supplied to said chamber to provide continuous cycles of charging and discharging of particulate material from said chamber,

3. The combination as specified in claim 1 wherein said pneumatic pressure means includes timer means for intermittent operation thereof in providing a pulsating discharge of particulate material by the conveyor system.

4. The combination as specified in claim 1 including a product collector interconnected with said conduit means at the discharge area end thereof for receiving particulate material discharged through said conduit mens, said product collector including valve means which may be closed during flow of particulate material through said conduit means for accumulation within said product collector of particulate material flowing through said conduit means and may be opened for discharge of particulate material from said product collector upon cessation of such flow of particulate material through said conduit means, said product collector also including vent means whereby to vent the pneumatic pressure of said conduit means and permit relatively compact accumulation of particulate mate-rial in said product collector.

5, The combination as specified in claim 3 including a product collector interconnected with said conduit means at the discharge area end thereof for receiving particulate material discharged through said conduit means, said product collector including normally open discharge valve means, said discharge valve means being operably interconnected with said pneumatic pressure means whereby to close said valve means during flow of particulate material through said conduit means for accumulation within said product collector of particulate material flowing through said conduit means and is permitted to open for discharge of particulate material from said product collector upon cessation of such flow of particulate material through said conduit means, said product collector also including vent means whereby to vent the pneumatic pressure of said conduit means and permit relatively compact accumulation of particulate material in said product collector.

6. The combination as specified in claim 5 wherein said discharge valve means is pneumatically actuated for closing thereof and is operatively interconnected with said pneumatic pressure means so that the closing force thereof is greater than the pneumatic pressure being discharged into said product collector through said conduit means.

References Cited by the Examiner UNITED STATES PATENTS 1,309,671 7/1919 Weaver 302 2,565,946 8/1951 Bozich 30255 2,673,011 3/1954 Rood et al. 222207 2,744,792 5/1956 Finn 30259 3,012,701 12/1961 Weber 222449 3,077,365 2/1963 Fischer 30228 3,197,261 7/1965 KauflFman 30255 ANDRES H. NIELSEN, Primary Examineri 

1. IN A CONVEYING SYSTEM FOR PARTICULATE MATERIAL, THE COMBINATION OF A PARTICULATE MATERIAL STORAGE RECEPTACLE INCLUDING MEANS FOR AERATING THE PARTICULATE MATERIAL RECEIVED THEREWITHIN AND MAINTAINING THE SAME IN A SUBSTANTIALLY FLUIDIZED STATE; A CONTAINER FOR RECEIVING A RELATIVELY SMALL CHARGE OF PARTICULATE MATERIAL FROM SAID STORAGE RECEPTACLE; MEANS INTERCONNECTING SAID CONTAINER WITH SAID STORAGE RECEPTACLE IN JUXTAPOSITION FOR GRAVITY FLOW OF PARTICULATE MATERIAL FROM SAID STORAGE RECEPTACLE TO SAID CONTAINER; CHECK VALVE MEANS FOR SEGREGATING THE CHARGE PARTICULATE MATERIAL OF SAID CONTAINER FROM THE PARTICULATE MATERIAL OF SAID STORAGE RECEPTACLE; CONDUIT MEANS INTERCONNECTED WITH SAID CONTAINER AND LEADING TO A DISCHARGE AREA; AND PNEUMATIC PRESSURE MEANS OPERABLY INTERCONNECTED WITH SAID CONTAINER FOR PNEUMATIC DISCHARGE OF A CHARGE OF PARTICULATE MATERIAL FROM SAID CONTAINER AND THROUGH SAID CONDUIT MEANS TO A DISCHARGE AREA UNDER SUFFICIENT PRESSURE TO SUBSTANTIALLY CLEAR SAID CONTAINER AND SAID CONDUIT MEANS OF PARTICULATE MATERIAL, SAID PNEUMATIC PRESSURE MEANS INCLUDING AN ELONGATED AIR NOZZLE MOUNTED WITHIN SAID CONTAINER AND HAVING A PLURALITY OF AIR DISCHARGE APERTURES SPACED THEREALONG IN JUXTAPOSITION FOR SUBSTANTIAL AERATION AND FLUIDIZING OF THE PARTICULATE MATERIAL CHARGE OF SAID CONTAINER ON ACTIVATION OF SAID PNEUMATIC PRESSURE MEANS, AND SAID CHECK VALVE MEANS COMPRISES MEANS FOR PREVENTING BACK FLOW OF AIR AND PARTICULATE MATERIAL FROM SAID CONTAINER TO SAID STORAGE RECEPTACLE ON ACTIVATION OF SAID PNEUMATIC PRESSURE MEANS. 